Yes, C6.5 and C7 are independent of each other and both work on the same computer… What I don’t know is if the various libraries and sound banks, along with aftermarket VSTs need to be doubled up or whether you could tell C7 to share with C6.5. (I think C7 was a 5G+ download, BTW.) So I just doubled up everything if you follow. It works great, turning either version on, closing it and opening the other but I surely have about 3G of data doubled up. (Waves is not a problem as far as doubling up the data because the plugins stay in in an independent folder - but you do have to copy and paste the V9 load app into C7.)